/*
    * Copyright 2018 the original author or authors.
    *
    *  Licensed under the Apache License, Version 2.0 (the "License");
    *  you may not use this file except in compliance with the License.
    *  You may obtain a copy of the License at
    *
    *         http://www.apache.org/licenses/LICENSE-2.0
    *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   */
  
  package org.openehealth.ipf.platform.camel.ihe.fhir.core.intercept.consumer;
  
  import org.apache.camel.Exchange;
  import org.openehealth.ipf.commons.ihe.core.atna.AuditDataset;
  import org.openehealth.ipf.commons.ihe.fhir.Constants;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.naming.ldap.LdapName;
  import javax.naming.ldap.Rdn;
  import javax.security.cert.X509Certificate;
  import java.security.Principal;
  
  /**
   * @author Christian Ohr
   */
  public abstract class AuditInterceptorUtils {
  
      private static final Logger LOG = LoggerFactory.getLogger(AuditInterceptorUtils.class);
  
      public static void extractClientCertificateCommonName(Exchange exchange, AuditDataset auditDataset) {
          X509Certificate[] certificates = (X509Certificate[]) exchange.getIn().getHeader(Constants.HTTP_X509_CERTIFICATES);
          if (certificates != null && certificates.length > 0) {
              try {
                  X509Certificate certificate = certificates[0];
                  Principal principal = certificate.getSubjectDN();
                  String dn = principal.getName();
                  LdapName ldapDN = new LdapName(dn);
                  for (Rdn rdn : ldapDN.getRdns()) {
                      if (rdn.getType().equalsIgnoreCase("CN")) {
                          auditDataset.setSourceUserName((String) rdn.getValue());
                          break;
                      }
                  }
              } catch (Exception e) {
                  LOG.info("Could not extract CN from client certificate", e);
              }
          }
      }
  }